Swift has had an interactive interpreter from v1. Even scripting in Swift was supported from the start.
What it really needed back then was ergonomic APIs for this kind of programming.
Why would anyone in 2014 adopt Swift as a quick prototyping/scripting language when you can just do os.path.join() in Python (Swift's path APIs have always defaulted to the NextStep–era stuff), or subprocess.run() (Swift still defaults to NSProcess).
Today, the picture is different; swift-subprocess and swift-system have improved things greatly.
Swift has had an interactive interpreter from v1. Even scripting in Swift was supported from the start.
What it really needed back then was ergonomic APIs for this kind of programming.
Why would anyone in 2014 adopt Swift as a quick prototyping/scripting language when you can just do os.path.join() in Python (Swift's path APIs have always defaulted to the NextStep–era stuff), or subprocess.run() (Swift still defaults to NSProcess).
Today, the picture is different; swift-subprocess and swift-system have improved things greatly.